Re: [PATCH v6 3/6] asm-generic: add generic seccomp.h for secure computing mode 1

AKASHI Takahiro
2014-08-22T00:38:21Z

On 08/22/2014 02:51 AM, Kees Cook wrote:
> On Thu, Aug 21, 2014 at 3:56 AM, AKASHI Takahiro
> <takahiro.akashi@linaro.org> wrote:
>> Those values (__NR_seccomp_*) are used solely in secure_computing()
>> to identify mode 1 system calls. If compat system calls have different
>> syscall numbers, asm/seccomp.h may override them.
>>
>> Acked-by: Arnd Bergmann <arnd@arndb.de>
>> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
>
> Reviewed-by: Kees Cook <keescook@chromium.org>
>
>> ---
>> include/asm-generic/seccomp.h | 28 ++++++++++++++++++++++++++++
>> 1 file changed, 28 insertions(+)
>> create mode 100644 include/asm-generic/seccomp.h
>>
>> diff --git a/include/asm-generic/seccomp.h b/include/asm-generic/seccomp.h
>> new file mode 100644
>> index 0000000..5e97022
>> --- /dev/null
>> +++ b/include/asm-generic/seccomp.h
>> @@ -0,0 +1,28 @@
>> +/*
>> + * include/asm-generic/seccomp.h
>> + *
>> + * Copyright (C) 2014 Linaro Limited
>> + * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + */
>> +#ifndef _ASM_GENERIC_SECCOMP_H
>> +#define _ASM_GENERIC_SECCOMP_H
>> +
>> +#include <asm-generic/unistd.h>
>
> While this isn't a problem for ARM, this should be linux/unistd.h for
> other architectures to get the right stuff.

I will fix it.

>> +
>> +#if defined(CONFIG_COMPAT) && !defined(__NR_seccomp_read_32)
>> +#define __NR_seccomp_read_32 __NR_read
>> +#define __NR_seccomp_write_32 __NR_write
>> +#define __NR_seccomp_exit_32 __NR_exit
>> +#define __NR_seccomp_sigreturn_32 __NR_rt_sigreturn
>> +#endif /* CONFIG_COMPAT && ! already defined */
>> +
>> +#define __NR_seccomp_read __NR_read
>> +#define __NR_seccomp_write __NR_write
>> +#define __NR_seccomp_exit __NR_exit
>> +#define __NR_seccomp_sigreturn __NR_rt_sigreturn
>
> Some architectures use __NR_sigreturn, so this will need to be
> adjusted in the future into:
>
> #ifdef __NR_seccomp_sigreturn
> #define __NR_seccomp_sigreturn __NR_rt_sigreturn
> #endif

I will fix it.

> After these changes, I was able to port x86 to using this
> asm-generic/seccomp.h too.

Thanks,
-Takahiro AKASHI

> -Kees
>
>> +
>> +#endif /* _ASM_GENERIC_SECCOMP_H */
>> --
>> 1.7.9.5
>>
>
>
>